Examkin

Question

Difficulty: MediumCardiovascular System

Match each clinical presentation of a patient in circulatory collapse with the most likely corresponding invasive hemodynamic profile (pulmonary artery catheterization findings) expected upon initial evaluation.

  • A 58-year-old man presenting with severe, crushing substernal chest pain, marked diaphoresis, and new ST-segment elevations in leads V1-V6.Decreased cardiac index, elevated pulmonary capillary wedge pressure, and increased systemic vascular resistance
  • A 32-year-old woman presenting with sudden-onset severe lower abdominal pain, vaginal bleeding, significant tachycardia, and a positive pregnancy test.Decreased cardiac index, decreased pulmonary capillary wedge pressure, and increased systemic vascular resistance
  • A 68-year-old man presenting with high fever, chills, severe costovertebral angle tenderness, altered mental status, and warm, flushed skin.Increased cardiac index, low-to-normal pulmonary capillary wedge pressure, and decreased systemic vascular resistance
  • A 45-year-old woman with a history of breast cancer presenting with progressive shortness of breath, elevated jugular venous pressure, and muffled heart sounds.Decreased cardiac index, increased right atrial pressure, and equalization of diastolic pressures across all cardiac chambers

Answer

The presentations correspond to cardiogenic shock (Left 1 -> Right 1), hypovolemic shock (Left 2 -> Right 2), distributive shock (Left 3 -> Right 3), and obstructive shock (Left 4 -> Right 4).
Each type of circulatory collapse (shock) produces a distinctive hemodynamic profile based on the initial physiological derangement (pump failure, volume loss, loss of vascular tone, or extrinsic compression) and the body's expected compensatory responses.

Step-by-Step Solution

1
Diagnose the underlying etiology of shock for each clinical vignette.
The patients have acute anterior myocardial infarction (cardiogenic), a ruptured ectopic pregnancy (hypovolemic), sepsis secondary to pyelonephritis (distributive), and cardiac tamponade from malignancy (obstructive).
Identifying the primary insult determines whether the shock is driven by pump failure, volume loss, severe vasodilation, or extrinsic restriction.
2
Correlate the etiology of the shock with its primary pathophysiological derangement.
Cardiogenic shock primarily features low contractility. Hypovolemic shock features low preload. Distributive shock primarily features low afterload (SVR). Obstructive shock features restricted ventricular filling.
The primary derangement dictates the initial hemodynamic changes.
3
Identify the compensatory mechanisms for each type of shock to complete the hemodynamic profile.
In cardiogenic shock, low output causes compensatory vasoconstriction (increased SVR). In hypovolemic shock, low volume causes compensatory vasoconstriction (increased SVR). In distributive shock, extreme vasodilation causes a compensatory increase in heart rate and contractility (increased cardiac output).
Hemodynamic parameters on a pulmonary artery catheter reflect both the primary deficit and the neurohormonal compensation.

Key Concept

Hemodynamic Profiles of Shock States
Rate this question

Topics

Cardiovascular System

More questions from this topic